Note: Descriptions are shown in the official language in which they were submitted.
CA 02476458 2004-08-16
Munich 18th February 2002
Our ref: AM5188 RF/MIM/ks
Applicants/proprietors:AVERY DENNISON CORP
Office ref: New application
Avery Dennison Corporation
North Orange Grove Boulevard, Pasadena, CA 91103, USA
'Application device for labels of varying length'
1o The invention concerns an application device for applying segments
of flat material, in particular labels, as set forth in the classifying
portion of
claim 1, and a method of applying such segments of flat material to a
product as set forth in the classifying portion of claim 12.
The self-adhesive labels which hitherto have usually been employed
in practice are customarily made by firstly producing a flat material web of
which one side has an adhesive layer and the other side can be printed
upon by means of a printing unit. In order to ensure that the self-adhesive
flat material web does not adhere to conveyor rollers, printing rollers and
the like in the printing unit for printing the labels, the self-adhesive flat
material web is covered with a carrier material web at the side of the
adhesive layer. That self-adhesive flat material web is generally wound up
to form a roll whereby handling of the self-adhesive flat material web and
storage thereof is facilitated.
Hitherto application devices have been used to apply predominantly
pre-stamped self-adhesive labels which therefore are of predetermined
dimensions in terms of length and width, in that respect the maximum
width of a label is predetermined by the width of the flat material web. Pre-
stamped labels of that kind can be applied continuously without stopping
the product to be labelled. If however labels of a different length are to be
3o applied to products, the application device or labelling machine has to be
converted, whereby the stoppage time of the application device and thus
the labelling costs per product are increased.
1
CA 02476458 2004-08-16
In the case of the so-called linerless labels the self-adhesive flat
material web does not have any carrier material web. Such a flat material
web can be rolled up like a conventional adhesive strip. That permits an
increased level of productivity by virtue of more efficient rolling and thus
shorter setting times. In addition linerless labels are particularly
environmentally friendly as there is no waste of silicone-bearing carrier
material. Further advantages are reduced cost in stockkeeping, transport
and waste disposal due to up to 50% more label material. In addition
linerless labels are not pre-stamped but are continuously drawn off a roll
io and cut to the required length. In that case, labels of differing lengths
can
be advantageously produced from the same flat material web.
Just as in the case of the linerless labels, it is also known in relation
to the labels which are produced from a flat material web with a carrier
material, for those labels not to be pre-stamped but to be cut off the flat
material web, according to the desired length.
If for example in industrial manufacture large numbers of products
are to be provided with labels of varying lengths at a high throughput rate,
the use of a self-adhesive flat material web lends itself to labels, with or
without a carrier material web, in a non-pre-stamped form. Accordingly an
2o application device in that use can produce labels of the desired dimensions
in an extremely flexible fashion and apply them to products.
The cutting operation which is necessary in that case for separating a
flat material segment from a flat material web with or without a carrier
material for the production of a label suffers from a serious disadvantage:
at each individual label the feed of the flat material web must be stopped
each time in order to permit the label to be separated in a trouble-free
manner. That involves stopping or at least decelerating the products to be
labelled, at the application device. The consequence of this is a lower
product throughput rate. Accordingly such a stop-and-go mode of operation
3o involves a higher level of material wear and energy consumption.
The object of the present invention is to provide a device and a
method of applying or putting on self-adhesive labels, wherein in particular
the labels can be applied continuously without stopping the products to be
2
CA 02476458 2004-08-16
labelled. The invention further seeks to provide a simple structure for the
application device and related thereto easy and trouble-free handling. In
addition the invention seeks to provide a maximum in terms of flexibility in
respect of the length of the labels to be applied.
In regard to the application device the foregoing object is attained by
the features of claim 1. Advantageous configurations of those solutions are
set forth in appendant claims 2 through 11.
The application device according to the invention has a buffer or a
buffer unit between a separatian unit for separating a flat material segment
1o from the flat material web and an application unit for applying such a flat
material segment in the form of a label to a product. The buffer or the
buffer unit advantageously decouples the operation of applying the labels to
the products from the separation operation which takes a finite period of
time. The cycle rate of the products to be labelled is thus independent of
the duration of the separation operation for a label.
The buffer or the buffer unit of the application device according to
the invention may include a variable loop which is formed from the flat
material web between the separation unit and the application unit prior to
each separation operation. The length of that loop represents the flat
2o material web portion which can be taken from the buffer unit and is at
least
of the length of the distance which is covered by the surface of a product to
be labelled, during the duration of the separation operation of the flat
material segment, at the application unit.
The loop is formed in the buffer unit by controlling the feed speed of
the flat material web in such a way that at least temporarily between two
separation operations it runs at a higher feed speed than the speed of the
products to be labelled, which are moved past the application device.
For that purpose the buffer unit has a controlledly driven feed roller
and a pressure roller which is spaced in relation thereto in the feed
3o direction of the flat material web. The feed roller can be arranged in the
detachment unit and serves for advancing the flat material segment at a
speed which is predetermined at any time. The pressure roller is provided
for pressing the flat material segments against the surface of the product at
3
CA 02476458 2004-08-16
the application unit. Both the feed roller and also the pressure roller are
arranged parallel to each other and to the plane defined by the surface of
the product. In that way a dispensed label is discharged by the application
device, advantageously aligned with respect to the surface to be labelled. It
is also possible to provide a controlled drive at the pressure roller.
For controlling the feed speed the application device can have a
control unit which inter alia controls the speed of the driven feed roller of
the buffer unit as described hereinbefore so that, between two separation
operations, that arrangement guarantees the formation of the loop of the
1o required length from the flat material web. To detect the feed speeds of
the
flat material web at the detachment unit, it is possible to provide at the
detachment unit a sensor which communicates the detected speed to the
control unit. Equally, it is possible to provide at the application unit or
the
conveyor device a sensor for detecting the speed of the products at the
application unit, which transmits the speed to the control unit.
The flat material web can comprise both a carrier material web on
which a self-adhesive label material web is disposed and also a carrier
material-less label web. In the embodiment with a carrier material web, it
is removed from the flat material web upstream of the separation unit.
2o In regard to the method the foregoing object is attained by the
features of claim 12. Advantageous configurations of the method according
to the invention are set forth in appendant claims 13 through 18. In regard
to the method, the advantages achieved are the same as have been
described hereinbefore with reference to the device.
Further advantageous configurations and an embodiment by way of
example are described hereinafter with reference to the accompanying
drawings. The terms 'left', 'right', 'down' and 'up' used in this respect
relate
to the drawings with the Figure designations in the normally readable
position. It is further to be pointed out that components of the same
3o structure and/or involving the same function are identified in the
individual
Figures by the same references. In the drawings:
Figure 1 is a diagrammatic side view of an application device
according to the invention, and
4
CA 02476458 2004-08-16
Figure 2 shows a detail view D from Figure 1.
Figures 1 and 2 show a possible embodiment of the application
device 10 according to the invention for carrying the application method
according to the invention into practice.
Figure 1 shows a diagrammatic side view of an application device 10
which is used to apply labels E or the like to at least a part of the surface
O
of products P which are moved by a conveyor device F past the application
device 10 in Figure 1 from right to left in a horizontally extending plane.
The housing il which surrounds the assemblies of the device 10 which are
1o described in greater detail hereinafter is partially removed in Figures 1
and
2. Only the substantially vertically extending rear wall 11a and a carrier
plate lib mounted thereon are illustrated.
In the illustrated embodiment of the application device 10 according
to the invention the labels E are made from a flat material web 20 which
comprises a self-adhesive label web 22 and a carrier material web 24 which
is disposed on the adhesive side 22a. The flat material web 20 is loaded in
the form of a supply roll RV into the device 10 by fitting the roll RV on to a
spindle A1 which is shown at top right in Figure 1 and which projects
perpendicularly from the rear wall l ia. The flat material web 20 is fed from
the supply roll RV by way of horizontally oriented guide rollers R1, R2, R3
to a detachment unit 30 which is not described in greater detail herein and
in which the label web 22 is detached from the carrier material web 24 by
being pulled therefrom at a dispensing edge. The 'empty' carrier material
web 24 is guided from the detachment unit 30 to a waste roll RA which is
shown at the right in Figure 1 and which is fitted on a spindle A2 projecting
perpendicularly from the rear wall 11a, and is wound up by the roll RA.
Adjoining the detachment unit 30 in the direction of conveying
movement of the flat material web 22 is a printing unit 40 which is not
described in greater detail herein and in which segments of the label web
22 can be printed upon with the desired information. That can take place
for example with a known thermotransfer printing process. A segment of
the label web 22, which is printed upon in that way, is then fed to a
separation unit 50.
5
CA 02476458 2004-08-16
The detachment unit includes inter olio a controlledly driven feed
roller 30a for the controlled advance movement of the label web 22 in the
direction of the separation unit 50 or an application unit 60 adjoining the
separation unit 50 in the feed direction. The label web 22 which is supplied
from the printing unit 40 is engaged by a guide which is not shown in
greater detail herein and then fed without slip by the controlled feed roller
30a which is controlled by a control unit (not shown) by way of the
separation unit 50 to the application unit 60 at a feed speed which is
defined at any time.
1o The application unit 60 substantially comprises a pressure roller 60a
which is oriented horizontally in relation to the plane defined by the product
surface O to be labelled and which presses the label E against the surface O
of the product P. The suspension means and guide means for the pressure
roller 60a are not shown in greater detail here. It should be noted that the
free-running pressure roller 60a can be resiliently mounted displaceably
reversibly in the direction of the surface of the product P so that at any
time a sufficient pressing force can be applied by way of the pressure roller
60a for fold-free application of the label E, The free-running pressure roller
60a can additionally be provided with a sensor element in such a way as to
permit the speed of the products P to be labelled to be detected. In that
way it would also be able to detect faults and problems such as an absence
of the products P. It will be appreciated that a sensor system of that kind
can also be provided independently of the pressure roller 60a.
Figure 2 shows the detail of the application device 10 of Figure 1 on
a larger scale. It is possible to see therein the separation unit 50 which
adjoins the printing unit 40, the application unit 60 and a possible
embodiment of a buffer unit 70 arranged therebetween. In this respect the
buffer unit 70 comprises the controlled feed roller 30a and the pressure
roller 60a, between which a loop 80 of the flat material web 22 can be
3o formed as a buffer, the loop 80 being variable from the label E to be
applied. The buffer unit 70 makes it possible to decouple the application
operation from the separation operation in respect of a label E. That is
achieved by the specific and targeted co-operation of the controlled feed
6
CA 02476458 2004-08-16
roller 30a and the pressure roller 60a of the buffer unit 70. The necessary
co-ordination between the feed speed at the feed roller 30a and the
conveyor speed of the product or products P is ensured by the control unit
(not shown) which has already been referred to above and which is
included in the application device.
The control unit ensures suitable time control of the feed speed of
the label web 22 in the separation unit 50 by means of the controlledly
driven feed roller 30a in relation to the speed of the product or products P
to be labelled on the conveyor device F at the application unit 60. That
1o provides for filling the buffer unit 70, that is to say forming the loop
80,
between two separation operations in the separation unit 50. In that
respect, in principle the feed speed of the flat material web 20 or the label
web 22 between two separation operations can be constantly higher than
the speed of the products P on the conveyor device F. That corresponds to
a constant speed profile, that is to say vE(t) = constant, of the feed speed
vE between two separation operations. It is however also possible to 'fill up'
the buffer unit 70 with a loop 80, with a speed profile of a different
configuration, that is to say vE = vE(t). Thus for example immediately after
a separation operation, beginning with a strongly accelerated feed
2o movement, the flat material web 20 or the label web 22 can be advanced
very quickly and can then be braked linearly or exponentially. As a
feedback means, the current speeds of the product or products P at the
application device 10 and the label web 22 at the separation unit 50 can be
made available to the control unit by way of sensors which can be provided
for example at the feed roller 30a, the pressure roller 60a and the conveyor
device F.
If the speed of the products P at the application device 10 is vP and if
the separation operation for separating off a label E requires the period of
time ot, then the loop length LSI which is to be accommodated in the buffer
3o unit 70 approximately corresponds to vP ~ ot. With the period of time tE
for
applying a label E the feed speed vE in a first approximation for forming the
loop must be at least (vP ~ tE)/(tE - ot). Due to dead times in the feed speed
control procedures the speed in practice is to be selected at a higher value.
7
CA 02476458 2004-08-16
The control unit guarantees the formation of the respectively required loop
lengths between two separation operations, by way of the drive speed of
the feed roller. If a constant feed speed, that is to say vE = constant, is
not
selected, then the length ISZ of the loop 80 produced in the buffer unit
corresponds to the integral over the speed profile vE = vE(t):
tE -4t
that is to say ISZ = JvE(t)dt
0
To achieve the desired decoupling effect IS1 < ISZ must be satisfied.
When applying a label E firstly a printed segment of the label web 22
is fed to the separation unit 50 from the printing unit 40. The segment of
1o the label web 22 is passed by the feed roller 30a (not shown) in the
direction of the surface O to be labelled of the product P. Due to the self-
adhesive property of the side 22a of the label web 22, it remains adhering
to the product P upon coming into contact with the surface O thereof. To
ensure that the label web 22 adheres securely and without folds, it is
pressed against the surface O of the product P by the above-discussed
pressure roller 60a which corresponds to the application unit 60. From that
moment on the end of the label web 22 moves with the surface O of the
product P at the conveyor speed vP. Now the control unit for less than (tE -
ot) causes the feed roller to operate at the feed speed vE = constant or, as
2o discussed hereinbefore, with a different speed profile vE = vE(t), whereby
more label web 22 passes through the separation unit 50 than is applied to
the surface O of the product P. In that way the loop of the buffer unit 70 is
formed with the required length preferably in the region downstream of the
separation unit as far as the application unit 60. By way of example the
control unit can 'recognise' by means of a timer function when the
necessary loop length is attained. As soon as the required loop length is
formed the label web 22 is stopped for at least the duration of a separation
operation ot. Subsequently thereto separation of the label E is immediately
implemented at the separation unit 50. That therefore avoids tearing or
3o damaging the labels E.
While the feed roller 30a is stopped the application operation at the
product P is continued by the label web 22 which is 'stored' in the
8
CA 02476458 2004-08-16
previously formed loop 80. It is possible for that reason to stop the label
web 22 for separating a label E without the product or products P which is
or are to be labelled having to be stopped or decelerated.
A further possible way of providing a buffer or a loop can be attained
if the strip speed of the product P to be labelled is accelerated or slowed
down, with the material web being advanced at the same speed at the
same time.
If three application devices are combined together in such a way that
the respective pressure rollers are respectively oriented horizontally in
io relation to one of the three sides of the products, which are in orthogonal
relationship with the plane defined by the pressure rollers of the application
units, then different labels can be applied simultaneously to all three sides
in one pass.
To conclude the principle and essence of the invention should be set
forth once again: in all possible embodiments in a time-controlled mode of
operation between two separation operations more label web is always
moved past the separation unit than is applied to the product to be
labelled. That affords a buffer which can be used up during the individual
separation operations.
9
